STOCKHOLM — Nokia Siemens Networks is selling its fixed-line broadband access business to Adtran Inc., the latest in a series of sell-offs, the company said on Monday.

Up to 400 engineering, R&D, sales and professional services staff are expected to transfer to Alabama-based Adtran as part of the deal, financial details of which were not disclosed.

Nokia Siemens’ portfolio includes DSL and GPON (Gigabit passive optical networking) products. The agreement also includes provisions for Adtran’s products to be included in Nokia Siemens’ offerings.

By acquiring the NSN unit Adtran aims to grow its business outside the U.S., which today represents only 10.6 per cent of its revenue, according to Gary Bolton, Adtran’s vice-president of global marketing.

The deal is expected to close by the end of April 2012, the companies said.

Total spending on broadband aggregation equipment jumped 12 per cent to US$2.1 billion during the second quarter, according to Infonetics Research. The GPON market is especially hot, and grew 56 per cent in Europe, the Middle East and Africa.

Nokia Siemens’ restructuring plan calls for the company to cut 17,000 jobs worldwide, as it aims to cut €1 billion (US$1.3 billion) in annual costs by the end of 2013. The company will focus on mobile broadband and related services. Other areas like its wireline business will be sold, Nokia Siemens said at the time.

While Nokia Siemens is shedding units, Adtran [Nasdaq: ADTN] is doing the opposite. In August, the company acquired Wi-Fi vendor Bluesocket, which Nokia Siemens’ staff will help sell once the deal is approved.